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LeetCode SQL Practice

EasySQL · PostgreSQL00:00
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Your question is LeetCode SQL Practice. Start with the requirements and the one table on the right.

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Problem

Business Context

KPIT's Connected Engineering portal receives email addresses from employees and external collaborators. Different address formats can refer to the same mailbox, so reporting must count each valid destination only once.

Task

Write a PostgreSQL query that calculates the number of unique normalized email addresses in portal_emails.

Requirements

  1. Remove every period from the local part before the @ symbol.
  2. Ignore the plus suffix in the local part, including the + character and everything after it.
  3. Count each normalized email address once and exclude rows where email is NULL.

Schema

portal_emails
ColumnTypeDescription
email_idPKINTUnique identifier for the submitted email row
emailVARCHAR(255)Submitted email address
Tablesportal_emails
Your solutionPostgreSQL
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